In the structure of an existing optical amplification module, as shown in FIG. 1, it includes, sequentially from the image side to the object side, a reflective polarizing plate 01, a first phase delay plate 02, a lens unit 03 and a second phase delay plate 04. In the lens unit 03, the optical surface adjacent to the second phase delay plate 04 is a transflective optical surface. In use, the optical image from the object side is transmissively amplified by the lens unit 03, then reflected by the reflective polarizing plate 01, and again amplified by the lens unit 03, and finally enters the human eye via the reflective polarizing plate 01. Moreover, other lens units that do not influence the phase delay of light are further set on either side of any one of the reflective polarizing plate 01, the first phase delay plate 02, the second lens 03 and the second phase delay plate 04. The lens unit 03 and other lens units constitute a lens assembly, which is the core part that influences the amplification effect on the optical image.
In order to provide a good user experience, an intelligent Virtual Reality (VR) wearable device needs to realize a wide field angle, a large eyebox, high-quality imaging effect and a compact ultrathin structure, etc. In order to achieve the above objects, the lens assembly in the structure of the optical amplification module needs to be optimized. However, the structure of the existing optical amplification module does not have an optimized design, thus it cannot be guaranteed that the above objects can be achieved in the whole range, that is, it cannot guarantee a good user experience.